modules less costly than the equipment, but it may well turn out that they are much more likely to support the restoration process technically and economically.

Within a given land restoration project, the modules could be established in rows in the most highly degraded areas. Young trees on the shaded side of these cylinders could be planted and subsequently nurtured by the periodic release of water and nutrients. On the sunny side of the modules, a variety of short-term economic crops could be established to add to the produce from the module. The labor needs for the module-based agriculture could also be used to tend the emerging ecosystems.

The approach based on the desert-farming module need not be static in the sense that the modules, having fed and watered the newly emergent vegetation including trees through their most vulnerable stages, could be shifted to new locations to repeat the process. In this way, the short-cycle biotechnology could spread its benefits to surrounding ecosystems over a larger geographic area.

For arid environments, such as the Moroccan coast, we have developed a bioshelter system to assist with diversifying an area ecologically. The bioshelter is a transparent climatic envelope or greenhouse structure that houses the fish and vegetable modules. Our prototype is a circular geodesic structure that functions as a solar still and as an incubator for the early stages of the ecological diversification process (Figure 39–5). These bioshelters can even operate where there is no fresh water. In this extreme case, the aquaculture modules are placed inside the climatic envelope and water from the sea is pumped through them. During the day, the

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